How does the hydrocyclone move inside?

 The hydrocyclone consists of a cylinder, a cone, a feed port, an overflow port and an underflow port.

The hydrocyclone works mainly by centrifugal sedimentation. The mixed material to be separated is fed into the hydrocyclone tangentially from the feed port of the cyclone at a certain pressure, generating a high-speed rotating flow field in the cylindrical cavity.

Due to the different specific gravities of the materials in the mixed material, the particles with large specific gravity are subjected to large centrifugal force, and move axially downward and radially outward along the wall of the hydrocyclone. After reaching the bottom of the cone section, they are discharged from the underflow port, that is, sand is settled, forming an external cyclone; the particles with small specific gravity are subjected to small centrifugal force, and move axially upward and radially inward inward, and are discharged from the overflow port at the top, thereby achieving the purpose of separating mixed materials with different specific gravities.

The basic forms of fluid movement inside the hydrocyclone are divided into external cyclone and internal cyclone, short-circuit flow and circulation flow. Short-circuit flow is formed due to the friction resistance of the wall, and is divided into short-circuit flow under the cover and short-circuit flow on the side wall. Circulation flow is caused by the small diameter of the overflow pipe. The existence of circulation flow gives the coarse particles in the inner vortex a chance to be sorted again, thereby improving the separation accuracy. Pang Xueshi and others believe that eliminating circulation flow is conducive to reducing energy consumption and accelerating the separation process.

Air column is a unique phenomenon in open hydrocyclones. The fluid filling the entire hydrocyclone space is one of the necessary conditions for the formation of air column. At present, the research on air column mainly focuses on the size and shape of air column, the formation mechanism of air column and the internal flow field of air column. At present, most scholars such as Chu Liangyin believe that the existence of air column is not good for improving the separation effect of hydrocyclone, but only consumes energy, and the strong turbulence around the air column makes the separation result unstable.